123 456 789 1101 1123 1145 1167 1189 2201 2223 2245 2267 2289 ABSTRACT Despite growing efforts to understand the role of the microbiota in airway disease, mechanisms that link microbial community dysbiosis to chronic inflammation remain elusive. Chronic rhinosinusitis (CRS) is a significant health problem in the United States, costing up to $65 billion each year and affecting up to 16% of the US population. CRS patients frequently present with pulmonary comorbidities suggesting that there are common underlying pathophysiologic mechanisms that contribute to upper and lower airway inflammation, known as the unified airways concept. In this proposal, we aim to understand the role of the upper and lower airway microbiota in driving concurrent immune responses in patients with CRS and asthma. Asthma is a common pulmonary disease that has strong clinical and epidemiological associations with CRS: Between 20%- 60% of CRS patients with nasal polyps have asthma. Dysbiotic microbial communities have been reported in sinuses of CRS patients and in the lungs of asthmatics, however, the microbiome or host immune response of these sites have not been examined in parallel. The goal of this proposal is to establish the existence of an upper-lower airway axis by sequencing the bacterial and fungal microbiome, profiling the host immune response, and through in vitro experiments that aim to identify bacterial metabolites in mixed-species culture that drive type-2 inflammation. Supporting the concept of a unified airway, our preliminary data show dysbiotic microbial communities in the upper and lower airways of CRS patients with asthma and concurrent type-2 inflammation shared across the airway sites. To expand these studies, we will use an integrated multi-omics approach to investigate the fundamental basis of microbiome structure and function in the context of the immune response of patient-matched upper and lower airway samples from CRS patients (with or without asthma) and healthy individuals that we have banked over the past four years. From these analyses, we will be able to infer the ecological relationships that contribute to chronic inflammation in concurrent upper and lower airway disease. In the second aim, we will determine whether and how pathogenic microbial communities drive or exacerbate airway inflammatory responses in vitro. We will characterize the metabolome in CRS/Asthma- patients and confirm these metabolites are of microbial origin in mixed species biofilm culture. To determine interaction with the host, we will sensitize peripheral blood dendritic cells (DCs) with CRS-Asthma associated metabolites, then co-culture DCs with nave T cells and quantify T cell differentiation. This study will contribute to our understanding of the upper-lower airway axis in unified airway disease and will ultimately lead to therapeutics aimed a manipulating the upper airway microbiome for treating concurrent sinus and lung disease.